1. Field of the Invention
The present invention relates to a method and apparatus for filtering unwanted substances from a gas, and more particularly, to the filtering of gas through a liquid such that unwanted siphoning of the liquid out of the filter cannot occur.
2. Description of Background Art
Traditionally, the filtering of gas through a liquid required either the use of a mechanical valve or a special inlet port designed to prevent the loss of the filtering liquid by siphoning due to a reversal of gas flow. All previous inlet port designs actually enter the filtering liquid thus failing to prevent a possible loss of filtering liquid due to siphoning of the liquid. A primary feature of the present invention is that the gas inlet port does not enter the filtering liquid and is therefore an anti-siphoning apparatus.
3. Summary and Objects of the Invention
Accordingly, it is a primary object of the present invention to provide an apparatus that uses a liquid to filter a gas to remove unwanted substances from the gas.
It is another object of the present invention to provide the filter device with at least two vessels containing liquid, each of the two vessels having two identical ports either of which may be used as an inlet port or an outlet port. Gas to be filtered may move from one port to the other through the filtering liquid such that the liquid will not be siphoned out of either port.
It is another object of the present invention to prevent the liquid barrier from being broken due to an application of either pressure or vacuum at either inlet or outlet port.
It is still another object of the present invention to provide a filter that uses a liquid to filter gas to remove unwanted substances from the gas without requiring mechanical valves, such that the liquid in the two vessels act as valves.
It is an even further object of the present invention to provide a filter wherein the flow of gas can be bi-directional, but only if the inlet port becomes the outlet port.
The objects of the present invention are fulfilled by providing an anti-siphoning liquid valve filter for filtering a gas, the filter comprising a first vessel partially filled with liquid, the first vessel including bypass means for enabling the gas to bypass the liquid in the vessel in a normal filtering direction and for preventing siphoning of the liquid from the filter vessel, means for directing the gas into the liquid in the first vessel in a second direction, and means for discharging gas from the first vessel. Further, a second vessel is partially filled with liquid, the second vessel including means for filtering the gas bypassed through the first vessel in a normal filtering direction by directing the gas into the liquid of the second vessel, means for discharging filtered gas from the second vessel in a normal filtering direction, and a bypass for enabling the gas to bypass the liquid in the second vessel and prevent siphoning of the liquid from the second vessel. Gas is forced through the first and second vessels, respectively, in a normal filtering direction, and gas is permitted to flow through the second and first vessels, respectively, in a second direction to prevent the siphoning of liquid from either of said first and second vessels.
The anti-siphoning liquid valve filter may further include an intermediary vessel partially filled with liquid and have additional means for filtering the gas in the first filtering direction only by directing the gas into the liquid of the intermediary vessel.
Uses of the anti-siphoning filter of the present invention include, but are not limited to, a gas mask, an exhaust gas scrubber, and a double-exhaust gas scrubber.
A method for the filtering of gas for a gas mask through a liquid includes the steps of:
(a) inhaling atmospheric gas at the gas mask by the user,
(b) bypassing the gas over a liquid partially filling a first vessel upon inhaling,
(c) directing inhaled bypassed gas through liquid partially filling a second vessel, whereby the filtered gas enters the gas mask for inhalation by the user,
(d) exhaling gas at the gas mask by the user,
(e) bypassing the gas over the liquid partially filling the second vessel upon exhaling, and
(f) filtering exhaled bypassed gas through the liquid partially filling the first vessel, whereby the filtered gas exits the first vessel to the atmosphere.
A method for filtering an exhaust gas from a reaction container comprises the steps of:
(a) exhausting contaminated gas from the reaction container,
(b) bypassing the gas over a liquid partially filling a first vessel,
(c) filtering the bypassed gas through liquid partially filling a second vessel,
(d) exhausting filtered gas from the second vessel,
(e) filtering the filtered gas exhausted from the second vessel through liquid partially filling a third vessel, and
(f) exhausting filtered gas from the third vessel to the atmosphere.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.